When most video content is played back on a personal computer (PC), a complete, ordered version of every video frame exists somewhere in the system or graphics memory. It is thus possible for an adversary to build a “screen scraper” which crawls through all of memory looking for contiguous video data. Once the video data is found, the screen scraper can copy the pixels to the hard disk and thus retrieve a pixel-perfect copy of the content being played.
Future content protection standards, such as those being proposed for High-Definition Digital Versatile Disc (HD-DVD) pre-recorded content, may require protection against the screen scraper class of attacks. Accordingly, there may exist the need for video content protection techniques to mitigate such an attack vector.